I have sunburn that looks like skin cancer?!?

It's probably not cancer but if you're concerned have it checked professionally. I wish I could tell you how to cover it but the truth is that the skin is damaged & will take time to heal. You could possibly make it worse by adding makeup. Try some aloe vera for faster healing and try not to burn anymore. P.S. Also, drink lots of water to moisturize your skin from the inside.